问题
changes ______in the city, and a lot of factories ______.
A:have been takenplace; have been set up
B:have taken place; have been set up
C:have taken place;have set up
D:were taken place; were set up
B:have taken place; have been set up
C:have taken place;have set up
D:were taken place; were set up
正确答案是：
